Anterior chamber stability of a novel phacoemulsification machine through the slit side view method.

PURPOSE: To evaluate anterior chamber (AC) stability of the UNITY Vitreoretinal Cataract System (UVCS) compared with the Centurion Vision System with ACTIVE SENTRY (CAS) using the slit side view (SSV) technique during a simulated occlusion break event.

SETTING

Zengyo Suzuki Eye Clinic, Kanagawa, Japan.

DESIGN

Experimental study.

METHODS

10 porcine eyes underwent testing with UVCS and CAS at intraocular pressures (IOPs) of 20, 30, and 40 mm Hg; vacuum limits of 550, 600, and 650 mm Hg; and an aspiration flow rate of 40 mL/min. Eyes with 2.4 mm incision were transferred to slitlamp. Continuous irrigation stabilized IOP before occlusion break which was simulated thrice. IOP changes and SSV images were recorded determining AC depth (ACD) changes, surge duration, and volume during an occlusion break event.

RESULTS

ACD change was significantly less with UVCS compared with CAS (0.15 ± 0.06 vs 0.43 ± 0.14 mm, P < .001). During occlusion break, minimum IOP was closer to baseline with UVCS vs CAS (19.1 ± 5.9 vs 26.9 ± 6.3 mm Hg, P < .001). Postocclusion break surge volume and duration were minimal with UVCS vs CAS ( P < .001), with mean recovery time ≤ 0.17 seconds with UVCS.

CONCLUSIONS

UVCS maintained AC stability better than CAS during simulated occlusion break testing which may improve clinical outcomes, surgeon confidence to operate at lower IOP. Recovering from postocclusion break surge faster than reported human reaction times suggested UVCS compensated for fluctuations faster than the surgeon can react.